In a HDD, a head-slider, which flies in proximity to the recording surface of a rotating magnetic-recording disk, reads and writes data. A lubricant is applied to a surface of the magnetic-recording disk in order to avoid, for example, mechanical damage due to a collision with the head-slider, corrosion or other chemical damage, and impurity adhesion.
In recent years, the lubricant applied to the magnetic-recording disk adheres to the head-slider due to a significantly decreased fly-height of the head-slider. Particularly, the head-slider flies in proximity to the recording surface of the magnetic-recording disk at such an attitude that a trailing-edge side of the head-slider is positioned closer to the magnetic-recording disk than a leading-edge side. Therefore, it is likely that the lubricant will adhere to the end of the trailing-edge side, which comes close to the magnetic-recording disk. This may alter the flying characteristics of the head-slider.
When, for example, a conventional head-slider 90 shown in FIG. 9 is used, the air-stream stagnates at the end of the trailing-edge side fo of the disk-facing side of the head-slider 90. As used herein, the term of art, “air-stream,” is used by way of example and not limitation thereto, and refers to a gaseous stream that may be used in the HDD. Air-stream stagnation arises because of a confluence of an air-stream, which arises due to the rotation of the magnetic-recording disk and flows over a deep-recessed surface 96, with another air-stream, which arises due to an atmospheric pressure difference between the disk-facing side and the outside of the disk-facing side and flows from the outside of the disk-facing side to the deep-recessed surface 96. Such air-stream stagnation produces lubricant adhesion and accumulation on the head-slider 90. If the lubricant accumulation becomes excessive, the lubricant accumulation may cover a rail surface 94b at which a magnetic-recording head 95 is disposed, which can result in read and write errors in the magnetic-recording process. Thus, manufacturing and development engineers are interested in means to reduce the effects of such lubricant accumulation.